Apparatus for refrigeration



Sept. 15, 1931. R. w. DAVENPORT INVENTOR. Ransom h/ flaw/300m A TTORNE Y.

Patented Sept. 15, 1931 UNITED STATES PATENT OFFICE RANSOM 'W. DAVENIOBT, OF DETROIT, MICHIGAN, ASSIGNOB TO CHICAGO PNEUMATIC TOOL COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY c APPARATUS IOB"REFBIGEBATION Application fled April '2, 1927. Serial m. 180,888.

cifically it relates to apparatus for separating out lubricant from the volatile refrigerant and restoring it to the lubricating system of the apparatus. It has particular adaptation to refrigerating systems utilizing a working substance having lubricant in solution and arranged to separate out the lubricant in a highly concentrated form at one point in the cycle by thermal means as disclosed in my copending application, Serial No. 88,164,

filed February 15, 1926 of which the present invention may be consideredin certain respects as an improvement. My aforesaid copending application discloses apparatus in cluding a member for condensing the vaporized refrigerant and a separate member connected between the condenser and the discharge port of the pumpacting to retain liquid discharged fromthe pump under the maximum temperature and pressure of compression a sufficient time to permit fractional distillation of the liquid.

One object of the invention is to provide improved apparatus for extracting lubricant in'highly concentrated form from the circulated working substance. Another object is to provide an improved arrangement for a concentrating still on the high temperature, high pressure side of a refrigerating system.

' Another object is to insulate such a still so that substantially all of the heat of compression is available for the therinal separating process which takes place therein. Still another obiect is to accomplish the desired results with simple and inexpensive apparatus.

The invention involves the utilization of thecondensing member of a refrigerating system to prevent loss of heatfrom the lubricant separating means to the room in which the apparatus is placed. To this end the still which comprises the separating means may be disposed at least partly within a portion of the condensing chamber. By utilizing a tank condenser of the type shown in my copending applications Serial No. 7 7,156,, filed December 22,1925 and Serial No. 78,563, filed December 31, 1925, it is possible to place the still entirely within the condensing chamber thereby adequately insulating the still without additional expense for this purpose and incidentally improving the compactness and appearance of the apparatus as a whole.

In order to illustrate the invention, one concrete embodiment thereof is shown in the accompanying drawing, wherein the single View shown a refrigerating outfit intended for household use in vertical section, the apparatus being shown generally in side elevation but having a wall of the condenser partly broken away.

In the outfit shown heat is withdrawn from the food storage chamber a of the refrigerator A by vaporizing a volatile liquid in a suitable evaporator 1 through the action of a pump or compressor 2 which discharges through a pipe 3 into a condenser 4, the products of the condenser being fed back to evaporator 1 through pipe 5 and feeding device or expansion valve 6. Pump 2, which may be of any suitable or desired type having its crank case under substantially uniform pressure, is arranged to be driven by an electric motor 7 through gear train 8, 9, and a fan 10 on the motor shaft may. be utilized to extract heat from pump 2 and condenser 4. Pump 2 has a lubricating system of any desired type (not shown) such as the splash system and lubricant is arranged to be fed to such system by a pipe 11.

In operating apparatus of the above type, lubricant soon works into the circulated refrigerant through leakage in the pump, and may be purposely in solution with the volatile liquid to form a working substance of the type disclosed in my copending application, Serial No. 60,311, filed October 3, 1925. In the apparatus shown at least a part of such lubricant is arranged to be separated out by thermal means after the manner disclosed in my aforesaid copendin ap plication, Serial No. 88,164, to replenis the losses incurred by leakage from the lubricat ing system. To this end outlet pipe 3 from pump 2 discharges directly into a still 12 intendedto operate at the high heat of comression and connected in series with condenser 4 To prevent loss of heat to the room in which the-apparatus is placed, condenser 4. is utilized at least partly to insulate still 12. To this end condenser & is in of compression a body of lubricant solution- 12a until it reaches equilibrium concentration. The height of this body of'liquid is determined by outlet port 11a which communicates' with lubricant feed pipe 11 extending to the crank case of compressor 2.

IAS shown pipe 11 is arranged to form a trap to rotect the crank case of the pump against the high pressure obtaining in still 12. The still has a second outlet port, 12?) for the gases and vapors in the still, which port communicates either directly, or through a pipe 13, with any desired part of the condensing chamber. A pipe, of substantial length, such as 13, delays the gaseous dischar e into condenser 4 and assists in-maintaining still 12 at the high heat of compression.

While the refrigerating apparatus disclosed may be arranged to operate on the conventional or Clausius-Rankine cycle, it preferably operates on the vapor-gas principle disclosed in my- Patent No. 1,619,196, March 1st, 1927.

While a preferred form of the invention has been herein shown and described, it is to be understood that the invention is not limited to the specific details thereof but covers all changes, modifications and adaptations within the scope of the appended claims.

I claim as my invention:

1. Refrigerating apparatus of the compression-expansion type comprising evaporator, a compressor and a condenser connected together to form a closed cycle system, said condenser being arranged to be externally cooled, said compressor having a lubricating system, and thermal means for separating out lubricant from the working su stance and restoring it to the lubricating system of said compressor, at least a part of said means being arranged to be insulated by said condenser against excessive loss of heat to said compressor.

2. Refrigerating apparatus of the compression-expansion type comprising an evaporator, a compressor and a condenser connected together to form a closed cycle system, said condenser providing an air cooled chamber, said compressor having a lubricating system, and thermal means for separating out lubricant from the working substance and restoring it to the lubricating y preference the hollow said means being disposed within said condenser chamber and out of heat exchange relation with saidcompressor.

3. Refrigerating apparatus of the compression-expansion type comprising an evaporator, a compressor and an externally cooled condenser connected together to form a closed cycle system, said compressor having a lubricating system, and means including a still for separating out lubricant from the working substance and returning it to said compressor, said condenser being arranged to protect said still against loss of heat both to said compressor and to the external cooling medium of said condenser.

4. Refrigerating apparatus comprising anevaporator, a compressor, and a condenser connected together to form a closed cycle system, means for extracting heat from the exterior of said condenser, means for utilizing said condenser for protecting the discharge of said compressor from heat losses to said compressor and to said heat exhausting means thereby to effect separation of lubricant from the working substance by fractional distillation, and means for delaying the compressor discharge in reaching said condenser after leaving said protecting means.

5. Refrigerating apparatus comprising. an evaporator, a compressor, and a condenser connected together to form a closed cycle system, said compressor having a lubricating system, said compressor and said condenser being remote from one another, means for separating out lubricant from the working substance by fractional distillation at the high heat of compression and for returning the separated lubricant to said compressor, said means including a still, said condenser providing a condensing chamber of substantial size and said still being disposed in said condensing chamber.

6. Refrigerating apparatus comprising an evaporator, a compressor and an air cooled tank condenser remote from one another but connected together to form a closed cycle system, means for separating out lubricant from the working substance at the high heat of compression'comprising a still disposed wholly within said tank condenser, and

means for feeding the separated lubricant to said compressor.

7 A closed cycle refrigerating system comprising an evaporator, a compressor, a condenser remote from said compressor provid liquidleading to said compressor and means for removing heat from the exterior of said condenser.

8. In combination, in a closed cycle system, an evaporator, a compressor, and a condenser remote from said compressor, said 7 condenser comprising a hollow member providing a condensing chamber of substantial size and having a smaller hollow membermounted therein for use as a still, a connectlon from said compressor to sald mner chamber, an outlet for vapor and gases from said inner member to said condensing chamber, an outlet for liquid from 581d inner member to thecrank case of said compressor, a connection from said condensing chamber to said evaporator including a feeding device,

and a connection from said evaporator to the inlet of said compressor. a

9. An apparatus unit for closed cycle systems of the compression type comprising nested hollow members, the one wholly within the other, the inner to receive the discharge of the compression means and for maintaining the discharge 'out of heat exchange relation with the compressing means so as to separate out lubricant in the discharge by fractional distillation, and a connection between the members for conducting gaseous residue into the outer member.

10. A combined condenser and still unit for aclosed cycle refrigerating system of the compression .type comprising a hollow member providing a condensing chamber of substantial size and having a smaller hollow member mounted therein for use as a still, an inlet to said smaller member for connection to the compressing means, two outlet connections from said smaller member, one to conduct liquid from said still and the other to conduct gas and vapor into said condensing chamber, and a single outlet connection from said condensing chamber, said larger uiember being adapted and arranged to 1nsulate the contents of said smaller member against heat losses to the compressing means and to the cooling medium for the exterior of the unit.

Signed by me atDetroit, in the county of We ne, and State of Michlgan this 31st day of arch 1927.

RANSOM'W. DAVENPORT. 

